diff --git a/CHANGELOG b/CHANGELOG
index fa4a2817b..5ca42a11b 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,8 @@
 #s wa Nmap Changelog ($Id$); -*-text-*-
 
+o [NSE][GH#1038][GH#1037] Script qscan was not observing interpacket delays
+  (parameter qscan.delay). [nnposter]
+
 o [NSE][GH#1046] Script http-headers now fails properly if the target does not
   return a valid HTTP response. [spacewander]
 
diff --git a/scripts/qscan.nse b/scripts/qscan.nse
index 5f857a6ef..ff41badc6 100644
--- a/scripts/qscan.nse
+++ b/scripts/qscan.nse
@@ -484,12 +484,9 @@ action = function(host)
 
       -- Unlike qscan.cc which loops around while waiting for
       -- the delay, I just sleep here (depending on rtt)
-      if rtt < (3 * delay) / 2 then
-        if rtt < (delay / 2) then
-          stdnse.sleep(((delay / 2) + math.random(0, delay) - rtt))
-        else
-          stdnse.sleep(math.random((3 * delay) / 2 - rtt))
-        end
+      local sleep = delay * (0.5 + math.random()) - rtt / 1000000
+      if sleep > 0 then
+        stdnse.sleep(sleep)
       end
     end
   end